1. Field of the Invention
This invention relates to an exposure control device in a camera, and in particular to an exposure control circuit in a camera which uses an analog-digital converter and a digital-analog converter to determine the exposure.
2. Related Background Art
In an example of the photometering circuit of a camera, a photocurrent flowing through a photodiode is logarithmically compressed and taken out by the use of an operational amplifier and a diode and the photometering output thereof is handled as the brightness of an object to be photographed, but such photometering output is varied by the ambient temperature even for the same brightness. So, heretofore, the analog output of the photometering circuit has been converted into a digital value, whereafter it has been temperature-compensated by a temperature compensating circuit for compensating for an input signal in accordance with the ambient temperature. Also, in an exposure control circuit designed such that the film speed input as digital information is converted into an analog amount and used for an exposure control operation, it is necessary to effect temperature compensation for the data indicative of the film speed, and a similar temperature compensating circuit is used. In such conventional temperature compensation, however, a temperature compensating circuit for exclusive use becomes necessary, and this leads not only to an increased number of elements but also to complication of the circuit.